Dazed and confused by 4DP Full Frontal test results

TL;DR: Did 4DP Full Frontal test today in Wahoo SYSTM. Got confused and disappointed with the outcomes. Refusing to accept a reality check, and looking for a way to prove this test wrong.

Hello my fellow FTP-obsessed overthinkers. Want to share experience and hopefully get an advice or two on how to cope with new reality.


I’m almost 40, 6’4’’ (193cm), 185lbs (84kg). Was never fit (but was never chubby either, genetics I guess), was riding casually, two years ago (give or take) started structured training and was riding more and more and more, now with some racing included.

FTP progression over two years wasn’t huge:

  • Started with 256W at sea level.
  • Moved to Colorado and didn’t loose much according to tests (so perhaps I gained few watts, but elevation change evened things out).
  • The peak I had at the beginning of 2023 was 266W here at 1 mile high.
  • During the season AI FTP detection ramped me up to 279 for better or worse. Must say, I don’t trust these numbers, but since I never struggled with workouts at a given intensity, maybe it wasn’t too far off.
  • At the end of the season (November) the ramp test came out at 264W which is a decline, but I felt tired to death, so I was kinda happy it didn’t go worse than that. Until today I was sticking to that number in my base training.
  • Winter training schedule is compromised by alpine skiing, not gonna lie, but I do believe I’m doing a good job keeping it balanced.

Here comes today

I had a good rest and carb load routine, did the openers yesterday, was really really looking forward to this torture. Leaving unimportant things aside, my test results are:

  • Max aerobic power (avg from 5 min steady at full gas): 342W (produced, not estimated).
  • 20 min avg — 242W. Because this 20 min long effort comes after two sprints and 5 min at VO2Max, SYSTM actually uses an avg power as rider’s FTP without taking 5% off as with the regular 20 min FTP test.
  • That puts my max aerobic power at 142% of my FTP which is precisely where it’s supposed to be, wow. Does it prove that the numbers are true? Hmmm.

But still, 242W? That must be a joke! I can confidently say that if I do 20 min in ERG mode at 255W (255W*0.95=242W) it will be hard but absolutely doable any day of the week with no special preparation required. And that’s probably a good moment to stop wining and ask some specific questions:

  • Should I accept that new number as my FTP? My concern is that it might be so off that it will compromise my workouts and make them too easy. It will take time for adaptive training to figure that out. With a schedule being compromised by other activities, that can take a really long time.
  • Should I do a ramp test? Sounds like an obvious answer, but I’m not particularly excited about doing another test. But also, see below why ramp test does not sound like the best thing to do.
  • Or should I do a threshold workout with something like 2x20 at my “old” FTP (or 1x20 at 105% of that) to prove things wrong and get my mojo back? Not that it sounds more fun than a ramp test, but since it’s more like apples to apples with a 20 min part of the test that I just did, it appeals to me as a more valuable proof than a ramp test.

Anyways, I will appreciate any opinions on that, roast me if you wish. Thanks.

As usual, questions are really needed to understand more:

  1. Why have you done the 4DP in the first place?

  2. What is your actual pending plan for training regardless of your FTP value?

    • Specifically, what apps, services and general direction are you headed? Maybe this relates to #1.
    • Mixing in a test from an entirely different system with the intent of heading down the TR path seems an odd choice, if that is where you are headed.
  3. Per your follow-up options, the question is what tests have you done in the past?

    • Broadly speaking a common recommendation is to pick whatever test protocol you prefer and stick with it. Using different ones and doing comparisons as you are doing has strong potential for deltas & associated confusion you have now.
  4. As an outside item to muddy the water, are you able to access the AI FTP Detection in TR?


Try the long form test and know for sure. Personally, I could never get the hang of pacing a 20 minute test nor get super accurate results. When you do 35-45 minutes at FTP then you know where you are for sure. This test is actually easier than a standard 20 minute test.


I also struggled with pacing a 20 minute test and found the KM test a lot easier to deal with mentally.

Chad asked the relevant questions above so I won’t re-do those. As someone that used to train on SufferFest/Wahoo, I have done the 4dp test a handful of times. My ftp (20 min) number on that test was always pretty close to what I would get on a regular 20 minute test or a ramp test or AI detection nowadays. My only thought on your result was that maybe you just had a much harder time that day at recovering after the 5 min test, but it shouldn’t be that hard to recover from only 5 minutes of effort even at full gas. How did your 1 minute go at the end of 4dp? Was that in the ballpark of what you thought it would be? Also, had you ever done 4dp before?

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I’m die-hard loyal to TR and everything else is just a way to mix things up, and/or to get another perspective. Training is fully driven by TR’s custom plan built by a plan builder. Most of the races this season are either “rolling road” or “climbing road” (even though they’re all gravel, lol). I’m on low volume masters now, but that’s only an absolute must part of the training. There’s always extra.

I do have access to AI FTP detection. 21 days ago it estimated me at 259W. Since then I’ve been training 4 times a week, still based off of my old 264W ftp. Sweet spot and threshold with some Z2 in between (last week a bit easier than the first two). Normal base training. Plus skiing two days a week. With that being said, maybe I didn’t gain much, but certainly didn’t drop 22W into the abyss.

Next try will only be possible in 7 days.

8 min test long long time ago. Ramp tests only ever since.

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I had a hard time recovering from that effort indeed. Can’t say I was “ready to rock” at the beginning of a 20 min part. So maybe it’s as simple as that.

I did not have any particular expectations about this part, was only thinking about 5 and 20 min. But it came out as 448W, which is higher than what SYSTM estimates based on FTP alone (even for my old FTP of 264W the estimated AC was 426W). That, and also the fact that I was able to ramp it up a little bit towards the end of the 20 min interval, makes me think that I perhaps didn’t pace myself well enough.

Nope, this was my first shot at 4DP. Never did a good old 20 min either.

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Here’s how my 4DP numbers have changed:
NM (5 seconds): 792W* → 1075W
AC (1 minute): 426W* → 448W
MAP (5 minutes): 342W* → 344W
FTP (20 minutes): 264W → 242W

(*) these values were estimates that SYSTM made based on the old FTP of 264W.

A.k.a. deadly sins #6. The only thing better would be to do a longer TT. I’d therefore call your FTP 255 W (at least) and move on.


Where did it say 142% of FTP is precisely where its supposed to be? Your 20 minute result seems very low compared to your 5 minute result, the app normally flags results outside of a certain percentage range based on their sample data.

NM (5 seconds): 1075W
AC (1 minute): 448W (130% of MAP seems reasonable)
MAP (5 minutes): 344W (142% of FTP, 77% of AC)
FTP (20 minutes): 242W (70% of MAP seems low, and suggests you took it to easy or totally blew yourself up on the 5m effort)

I’m always minded to cut the developers of these programs a bit of slack and just say use your 4DP results to base your wahoo training on and your ramp test results to base your trainerroad training on.

I think we all tie ourselved in knots trying to make the results of these tests equivelent not helped my the fact they all call the result “your FTP” but as long as they are determined in different tests they cant be the exact same thing and are all just an estimation of an athletes “real FTP” - whatever that means :slight_smile:

Looking at these results it looks as though your power profile is biased towards short high-power efforts. This would lead to a higher number “FTP” on a ramp test than it would on a longer steady effort test or protocols that have hard efforts at the start with the aim to deplete the anearobic contribution.

But to my initial point, if you trust the developers of these products it doesnt matter. Both have steps to mitigate for athelets that dont fit the bell curve - 4DP on wahoo and progression levels on trainerroad.

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Whatever you think your FTP is,…try and ride at that for about 40mins, if can’t do that whilst rested then likely FTP is lower than you think. Equally if find this pretty easy then FTP likely bit higher. Repeat process!


Haven’t checked those numbers but indeed. If you - the OP - are more of a powerful in short durations kind of human and less of a endurance rider, those “results” from Wahoo system (4DP) and Trainerroad (AI/ramp) would co-exist very nicely.

Let me speculate:
I don’t know which TR plan you are on but I would assume (as typically TR workouts are shaped) it’s interval heavy and also Endurance Rides/Zone 2 are maximum 1 (maybe 1.5) hours long in your plan. Absolutely no problem for you to do these with a relatively high anaerobic prowess. So the TR ramp test results and AI assumptions would match with your aptitude for such shortish intervalls.

On the other hand if you were to do some longer (more helpful) Zone 2 and Tempo workouts making you a more well rounded athlete you would probably quickly discover that those would be too taxing when getting scaled by your TR ftp numbers. And they would probably much more in line with the 4DP derived FTP number.

In any case: like another contributor in this thread wrote: go with the numbers of the respective program / system you are getting your workouts laid for you. As it should be matched more or less at the end of the day, given both are somewhat sound and applicable to your situation.

(Edit: gosh, this forum software cracks me up. I swear and indeed see that my post here is a direct reply to JonGreengras. As it is also showing with that little arrow on the right side at the top of this post. But if you look at the post (not only at a glance) you are invaringly under the impression I replied to mcneese.chad… :frowning: While I don’t post much in here I’m a very seasoned internet and forums user all across the place for what it’s worth…)

I edited your post and removed the quote since it was not related.

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It’s not.

Ok… more biased towards short high-power efforts than whatever model wahoo uses to predict the curve based on FTP… just going from the below numbers.

Thank you :slight_smile:

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To the OP, do you feel like you’re getting a good training stimulus at your higher pre-4DP power? It sounds like the answer is yes. If so, I’d stick with that number for your TR workouts.

I think of the AI FTP number as a set point to determine the intensity of my workouts, not necessarily a precise FTP. If your workouts are hard but doable, and you’re progressing over time (sounds like “yes” to both) then who cares if a different test gives you a different number? It’s not like you suddenly got weaker. You say you’re a dedicated TR user, so stick to the number TR uses to set your workouts.

Only those using power profiling, quadrant analysis, TSS/the PMC, etc., all of which are predicated upon having more than “just a number”.